Vol 54(2020) N 5 p. 739-748; DOI 10.1134/S0026893320050088
E.E. Sokolova1, P.K. Vlasov2, T.V. Egorova1, A.V. Shuvalov1, E.Z. Alkalaeva1*
The Influence of A/G Composition of 3' Stop Codon Contexts on Translation Termination Efficiency in Eukaryotes1Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991 Russia
2Institute of Science and Technology, Klosterneuburg, 3400 Austria
Received - 2020-02-27; Revised - 2020-03-20; Accepted - 2020-03-26
Translation termination is a finishing step of protein biosynthesis. The significant role in this process belongs not only to protein factors of translation termination but also to the nearest nucleotide environment of stop codons. There are numerous descriptions of stop codons readthrough, which is due to specific nucleotide sequences behind them. However, represented data are segmental and don't explain the mechanism of the nucleotide context influence on translation termination. It is well known that stop codon UAA usage is preferential for A/T-rich genes, and UAG, UGA-for G/C-rich genes, which is related to an expression level of these genes. We investigated the connection between a frequency of nucleotides occurrence in 3' area of stop codons in the human genome and their influence on translation termination efficiency. We found that 3' context motif, which is cognate to the sequence of a stop codon, stimulates translation termination. At the same time, the nucleotide composition of 3' sequence that differs from stop codon, decreases translation termination efficiency.
stop codon, 3' context, translation termination, stop codon readthrough, ribosome